Acyl- physicochemical properties from

Apart from their position in membranes the acyl moieties, their chain length and degree of saturation influences greatly the physicochemical properties of the bilayers. Phosphatidylcholines with. short acyl ehain.s... 

The history of the physicochemical properties of A -acylamino acid started from the patent by Hentrich et al. [27], Since then, Staudinger and Becer reported the solubility and viscosity of A -acylsarcosinate [28] Naudet measured the surface tension and interfacial tension of aqueous solutions of A -acylseri-nate and At-acylleusinate [46], Tsubone measured the surface tension and critical micelle concentration (cmc) of various A -acylamino acids and investigated the effect of structural differences of amino acids and length of fatty acid residue on these surface activities [29], Heitmann [30] further investigated the cmc of Af-acyl cysteine, serine, and glycine and indicated that the-SH in cysteine stabilized the micelle structure with its hydrophobic nature. Ooki reported the surface activities of At-acylsarcosinate [47]. 

The overall physicochemical properties of ether glycerophospholipids are similar to those of ester-bonded glycerophospholipids except for differences in the phase transition temperature from gel to liquid crystalline and from lamellar to hexagonal phases. These differences may be responsible for determining physical properties of biomembranes such as bilayer thickness, area per molecule, acyl chain packing, free volume, and lateral domains (Paltauf, 1994 Lohner, 1996). In artificial membrane systems there are close similarities... 

Table 2. Physicochemical Properties of Acyl-(Acyl-Carrier Protein) Glycerol-3-Phosphate Acyltransferase from Higher Plants... 

Synthetic phospholipids are commercially available and they contain polar heads occurring in nature and and the same type of fatty acid in both, 9 -l and sn-2 sites. The acyl chains may be mainly myristoyl (C14 0), palmitoyl (C16 0), olcoyl (C16 l) or stearoyl (C18 0) residues. The physicochemical characteristics of the lipidic bilayers that are prepared from synthetic phospholipids are well defined. The lipid composition influences many physical properties of model membranes and it has been shown that single synthetic lipids or mixtures of short and long fatty acid chains can produce stable lipidic bilayers and liposomes. 

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